The Unknown
by Caskkett
Summary: When that elevator door opened, Kate and Castle felt something shift in the air.
1. For the First Time

THE UNKNOWN

On a warm and sunny summer day in the NYPD's 12th Precinct, Detective Kate Beckett was sitting at her desk doing the paperwork from the last case she had solved. Novelist Richard Castle sat in his chair next to hers, gazing at her hand writing the final words of that sheet, wanting to get them home to have some alone time. Detectives Kevin Ryan and Javier Esposito were playing paper football, like they always do, leaving their paperwork for later. Captain Victoria Gates was also doing her paperwork and making calls like it was a normal day. But what they all didn't know was that in a few minutes, one of their worlds will be turned upside down.

By the time all of their paperwork was done, the clock had struck 7 pm. All the detectives and the novelist decided to call it a night. As they were gathering their belongings to head home, the elevator had reached their floor letting someone out. No one was expecting anyone at this hour. No one could see who it was. As the shadow had walked closer and closer, they saw it was a teenage girl, about 15 years old, wearing rags for clothes and carried a dirty backpack with broken zippers. She looked like she never had a shower in her life. She stopped as she saw all the adult figures staring back at her. She started to shake as her eyes made it to the one and only, Kate Beckett.

"Uhh… I need to…ummm…" she couldn't help but stutter. She knew what she had to say but couldn't comprehend it in her mind.

"Hi sweetie," Esposito had started to say, "are you lost? Do you need help?"

"I umm… I need to talk to…" She stopped as Kate was looking worriedly at her.

"It's okay, you can talk to us. We won't hurt you. You can trust us, I promise." Esposito had said getting closer to the terrified girl.

The teen had finally cleared her throat, took a deep breath, and finally said" I need to talk to Kate Beckett."

Kate's face turned pale. She didn't know the girl and had never seen her before in her life. She knew she had to talk to her in case it had to do with another murder.

"That's me." Kate said confidently, "What can I help you with."

"I need to talk with you in private…please." The girl was begging now.

Castle had this look in his eye, like he had met her before or she looked familiar. But he couldn't put his finger on it.

"Okay let's go to the break room then." Kate said, leading the way to the room, "Can I get you anything?" she had asked the girl, looking back at Castle's worried face.

"I'm okay, thank you," the girl said looking at Kate close the door, "If you want to, you can ask your boyfriend to come in if it makes you feel better. You seem nervous about what I want to talk about."

Kate's eyes went down to the girl who was now sitting on the couch. She was…well she didn't know how to feel with that comment. "Umm…I … but… how did you… Castle? You wanna come in here please?" Kate didn't what to say to her yet.

A surprised Castle had obeyed his partner's command to go into the break room and closed the door behind him. "What's going o…" He had started off to say, only to be interrupted by Kate saying "I have no clue."

The girl had stood up when he walked in. She noticed both of their puzzled faces staring at each other. "I think that you too need to sit down for this." She sounded more adult then she did before. Like she knew what she wanted to say now.

The couple had sat down on the black velvet couch, grabbing each other's hand preparing for what was going to come.

"Let me start off by telling you a little bit about me," The girl had grabbed a chair and pulled it in front of them. "My name is Molly and I'm 15 years old. I came from a small town in Connecticut…well I was. Last week, I was walking home from school and I…" Molly cuts off and starts to cry.

"Molly, what happened?" Kate said in a soft tone, like Molly was her child.

She wiped a tear away from her face and started to speak again." I was walking to the corner store where my mother had owned. I was going in for my shift to let my mother off duty. I knew something was wrong when I walked in. She wasn't there waiting for me. I had walked to the back to see if she was there and… I saw her body. It was lifeless in a pile of boxes and in a pool of blood. There were stab wounds all over her…" Molly stopped again. She's balling this time.

Kate was speechless. The vision in her head haunts her now. She's replaying the words Molly had spoken in her mind when she reached a specific detail: stab wounds all over the body. She grabs Molly close for a hug, knowing what she had been through.

Kate broke away with a tear running down her streak and little sniffles. She looks over at Castle, who now is looking at the girls, side by side. She knows that look. It's the look that he made a connection.

Molly lifted her head, and looked at Kate and only Kate. "That's not why I am here though. Listen Kate, I have known about this since I was 5 and I know you have no clue. You need to know this and I knew I had to tell you when I saw the body." Molly said with a brief pause, "Kate…" Molly couldn't say it. She was regretting showing up alone.

Castle finished her sentence with an astonished look on his face, "You guys are sisters."


	2. Knowing the Truth

THE UNKNOWN: CHAPTER 2

"Castle, what did you say?" Kate quickly questioned him still staring back at Molly who did not seemed surprised he figured it out.

"Kate," he said softly, tugging her hand so she got closer, "I said you and Molly are sisters. I can see the resemblance of you in her and vice versa. The curly brown hair, the hazel colored eyes. It's all there right in front of me."

Kate's and Molly's eyes met. Kate was looking at Molly, seeing the resemblance within in them. Molly was just watching Kate, expecting questions any second from either one of them.

"Listen," Kate started off, "I think that we would be more…comfortable at one of our places. Why don't you come with us and we can grab a bite to eat and start making things…clear for us." She finished closing her quivering mouth.

"I think that is a good idea but I do have a problem…" Molly was at a loss of words when she finished that phrase.

"What is it? Maybe me or Kate can help." Castle suggested.

"I…I…I don't have anywhere to stay tonight. I can't go back to Connecticut. The memories and…" she stopped for a second, looking at Kate," and what if they come after me."

"You can stay with me. I mean…if we are sisters we need to have some bonding time…I mean…" Kate was too, at a loss of words. She didn't want to hurt the poor teen's feelings.

"Kate, I think the boys left so I'll go and get our jackets and paperwork." Castle offered, letting go of her hand and standing up. He looked down for a response. She gave a nod.

As the door closed, Kate finally blurted out something. Something she didn't want to say. Not just yet.

"Are you sure were related? I mean I see it but…I… I'm just confused how. Wait.. I didn't mean it...I...I'm sorry Molly. I hope you understand I'm not trying to hurt your feelings…" Molly cut her off.

"Kate," she said as she took Castle's seat, "I wouldn't expect anything else. I wonder what my mom had to deal with when she told me 10 years ago…" she choked up as memories flooded her mind. Tears were forming and Kate brought her in for a hug, like she knew what she was doing when in reality, she had no clue.

"Let's go and get the food now. Are you hungry for anything in specific?" Kate asked, trying to become more of a sisterly figure.

"Well I know you like Chinese food…" Molly said as Kate opened the door for her to meet Castle by her desk.

Kate looked puzzled. Not that many people knew that. Molly continued on "I know your favorite place is over by Castle's place. Sorry if that comes off kind of…stalking. Trust me I wasn't. I just know how to do research and before I moved to Connecticut I would..." she stopped herself from going too far. She couldn't say that with Castle there.

"Okay then, Chinese it is!" Castle declared as he pulled out his phone to order but before he hit he green call button on his phone, he stopped and said "I'm going to order from the place by my loft. Why don't we eat at my place and stay there so you 2 don't have to go back out into traffic. I have the guest room and Alexis's room so…" Kate grabbed Castle's hand, interlocking fingers.

"Thank you Rick." She said as she looked up at him, only a few inches apart. "Is that okay with you Molly?"

"It sounds great. You two are being so nice when I just barged into your life, making it all so different. I feel guilty now and…" Kate stopped her.

"Molly! Stop it!" she said as an older sister, "Yes you changed lives in a matter of minutes but it was a good reason, not bad. Stop putting yourself down. I will do anything for people I care about, and it includes you now." Kate exclaimed as she walked onto the elevator.

"Kate. Thank you." That was all Molly could say. She didn't expect Kate to become so fond of her so quickly. When Castle let go of her hand to press the lobby button, she stole a hug. Molly finally had someone there for her, 24/7 and she wasn't going to let that change for years.

About 30 minutes later, they were at the loft eating their Chinese food, and just talking. The couple showed the teen the bathroom and when she came out, she had a needle in her hand, worrying them Nothing big and nothing about what they talked about in the precinct. Castle had surprised the girls by making chocolate chip cookies as they caught up. Well as Kate learned about Molly. Molly had done her research and knew everything. She knew about her mother, when she got shot and her and Castle. She promised not to bring it bring it up in front of Gates. Kate leaned that Molly was a freshmen in her school, actually the high school where Alexi had recently graduated from. She did have diabetes, which is why she had gone to the bathroom to give herself insulin. Kate had also learned she lived without a dad and her mom had a hard time supporting the both of them and that's why they moved.

"The cookies are done!" Castle had said from the kitchen, pulling a tray of oozing chocolate chip cookies. Castle was glad that Kate knew she had more family. He could hear them getting along in the living room, laughing and whispering away. He stayed in the kitchen on purpose. They needed time alone. He had already decided that this is personal and is not Nikki Heat material.

Kate and Molly walked to the kitchen island, where there were 3 cups of milk and about 4 cookies on each plate. Kate smiled when she saw Castle. She knew he would be there to support her no matter what. They loved each other and that was all they needed. While they ate their cookies, Molly decided that it was a good time to explain exactly how she was related and everything that led her to them.

"Kate, I know I would have to tell you sooner or later so I'm going to start now. You deserve to know." She stated off as they all sat down, Castle reading one of his colleagues books knowing he didn't really need to know. "Rick, you can listen, it's okay." Molly said reassuring him. "I was 5 when I first started to ask my mom about dad. She told me that for my 9th birthday she would explain. I waited all 4 years. Before I went to bed that night, I asked her again and reminded her of that promise. She told me that your parents and she were close. She never knew about you because.. Well she didn't know. She said after the murder, your Dad needed to go out. They went to an Irish pub and started to drink. She had no clue dad started to drink that much and in the end, they were both drunk. I guess someone was watching you because she told me they made it back to her apartment down the street and well… I guess made me. She never told your dad and when he first saw her pregnant, he thought it was a one night stand with someone else. Then after I was born, they never spoke again because of me. By the time I was 13, she told me his name is Jim Beckett and he was a lawyer in the city. I went to the library for months and learned about your dad and then I came across an article about one of the Heat books and both of you were mentioned. A few weeks later, you were shot. I wasn't there but I was down the street and I was asked questions. "Molly paused and ate a cookie and continued, "I… had heard your conversation in the hospital. How you thought you were ugly and he thought he would never see you again. I waited until you fell asleep and then they let me see you. You were gorgeous. I saw the resemblance and I knew we were sisters. The next month, I moved. I came back every so often because this was my real home and plus I stayed in school here. I saw you walking around and I think one time on a date. Then when I went back to Connecticut, I had to stay in school there but it wasn't for long. It was about 2 months. It was like the killer knew I would walk in and see. Sorry I'm rambling but that's the whole story." She stopped talking and Kate and her were just thinking.

Castle had been cleaning the dishes when the story was done and wanted to hear Kate speak but knew she was speechless. He looked at the clock and saw how late I was getting.

"It's already 10:30? Time flies! Molly, do you want me to show you to the guest room?" Castle suggested but Kate replied for her.

"I got it Castle. I'll meet you in a few minutes." She said with a slight smile.

"Mr. Castle?" Molly finally spoke up, "Thank you. For everything." Molly hugged him tightly and Kate smiled.

"Anything for you. Oh! Molly? Call me Castle or Rick." He said letting them go up the stairs.

He watched them walk up the staircase, each foot step in sync with each other. He turned the hallway light on for Kate and walked to their room.

Up in the guest bedroom, Molly put her bag down on the bed and sat down. Kate sat next to her feeling that Molly had to tell her something.

Kate started off the conversation. "The double door is the closet and that single door is the bathroom. There's already a toiletries in there for you and blankets are in the hall closet. You think you're going to be okay?" Molly looked up into her eyes. It was almost like looking in a mirror.

"Kate, there was one thing I didn't mention. I couldn't with Castle there." She stopped making sure Kate was all ears.

"I'm listening, keep going." Kate said with a smile, knowing Molly was starting to trust her.

"I already know Castle but he doesn't remember. About 4 or 5 years ago, Alexis use to be my tutor. This was before I knew about you but he was talking to Alexis about this Beckett person and it was you. That was another way I heard about you. I don't know if I should tell him. It's just so…" Kate cut her off, trying to calm her nerves.

"I'll tell him when I go back down, Okay? I'll explain it a way he can understand. I knew he must of recognized you from somewhere when you walked into the precinct. Molly, thank you." They hugged it out.

"Well I'm going back down for some rest, if I can get any. If you need anything just come and get me. Sleep well Molly."

"Thank you Kate, you too." Molly said with the biggest smile she has seen that girl show off.

After that was said, Kate walked out and down the stairs. She walked to the room where he way lying down, waiting for her. As she put her hand on the door handle, she whispered to herself "Here we go." and opened the door.


End file.
